Impedance and modulus spectroscopy of polycrystalline Ba0.9995La0.0005TiO3 for multilayer ceramic capacitor

Ba0.9995La0.0005TiO3 ceramics prepared via solid-state reaction route was found to be phase pure at the final sintering temperature of 1300°C for 16 hours. The dielectric constant was varied from 1900 to 2800 from 10 Hz to 100 kHz. Impedance spectroscopy is a powerful technique to study the complexities of ceramic materials such as homogeneity and inhomogeneity of materials that being process during production of most electronic materials. An electronic ceramic component can be visualized as a grain, grain boundary and electrode system. Impedance spectroscopy is being widely used to separate out contribution of the bulk and the grain boundary to the overall equivalent circuit models. Fixed frequency plots of dielectric constant versus temperature for Ba0.9995La0.0005TiO3 ceramics shows typical perovskite response with Curie temperature, Tc about 115 °C and fit with the equivalent circuit which contributed by bulk and grain boundary response.